Goodwill And Other Intangibles (Schedule Of Change In Carry Amount Of Goodwill By Business Segment) (Details) - USD ($) $ in Millions	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 5,316	$ 3,909
Acquisitions	1,188	1,486
Divestitures		(142)
Foreign currency translation and other	(49)	63
Goodwill, ending balance	6,455	5,316
Automation Solutions [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	4,704	3,160
Acquisitions	696	1,486
Divestitures		0
Foreign currency translation and other	(45)	58
Goodwill, ending balance	5,355	4,704
Commercial & Residential Solutions [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	612	749
Acquisitions	492	0
Divestitures		(142)
Foreign currency translation and other	(4)	5
Goodwill, ending balance	1,100	612
Climate Technologies [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	555	553
Acquisitions	118	0
Divestitures		0
Foreign currency translation and other	(3)	2
Goodwill, ending balance	670	555
Tools & Home Products [Member]
Goodwill [Roll Forward]
Goodwill, beginning balance	57	196
Acquisitions	374	0
Divestitures		(142)
Foreign currency translation and other	(1)	3
Goodwill, ending balance	$ 430	$ 57

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Amount of increase in asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized resulting from a business combination.

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Amount of increase (decrease) from foreign currency translation adjustments and purchase accounting adjustments of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (g)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 25
-Paragraph 16
-URI http://asc.fasb.org/extlink&oid=84229725&loc=d3e961-128460

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
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-Section 50
-Paragraph 1
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-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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Amount of divestiture of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

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